Two-factor verification means users have to enter a second code when logging into a service. After entering your password, Apple will send a text to your phone and you'll have to use that as well to log in.

The improved security means that if a hacker gets your password and tries to log in to your iMessage or FaceTime account, the hacker would need your phone for the security code.

The security question system was the weak part of Apple's system. Hackers used publicly known information about celebrities to guess the answers and get into accounts. Adding two-factor verification to iMessage and FaceTime means users need to approve login attempts on their phone — making iCloud more secure overall.